Mill-burr



L. P. & G. TEED.

ILL BU'RB.

No. 308,108. 7 Patented Nov. 18, 1884.

. NITED STATES- PATENT OFFICE.

LORENZO I. TEED AND CHARLES TEED, OE ERIE, PENNSYLVANIA.

MILL-IBURR.

SPECIFICATION forming part of Letters Patent No. 308,108, dated November 18, 1884.

Application filed March 26, 1884. (No model.)

To all whom it may concern.-

Be it known that we, LORENZO P. Tenn and. CHARLES TEED, of Erie, county of Erie, and State of Pennsylvania,have invented a new and useful Improvement in Mill-Burrs; and We do hereby declare that the following is a full, clear, and exact description of the invention, which will enable others skilled in the art to which it appertains to make and use it, reference being had to the accompanying drawings, forming a part thereof.

Our invention relates to improvements in metallic mill-burrs; and it consists in the construction of the parts, hereinafter described and claimed. a I v The objects of our improvements are, first, to bring the heaviest grinding at the nearest convenient point to the center of the grindingsurfaces; second, to allow 'none of the grain to escape unground; third, to facilitate easy renewal of any one portion of the grindingsurfaces without causing the renewal of the whole. WVe attain these objects by the means illustrated in the accompanying drawings, in which.

Figure 1 is a plan view of one of our improved plates. Fig. 2 is a sectional elevation -of the metallic burr attached to a millstone.

Similar letters refer to corresponding parts in bothviews.

Upon the surface of the millstone A are affixed our sectional plates B B, the surfaces of which have compound curves along the radii. In our arrangement we bring the convexity of the compound curve to within about three inches of the center C,which arrangement we consider the best, as it brings theheaviest grinding surfaces nearest together at this point, and therefore the heaviest grinding is done near the application of the power, and consequently does not need as much power as when the heavy grinding is done nearer the periphery of the grinding-surface.

On the surfaces of the plates are furrows B, extending from the center C to within about oneeighth of an inch of the peripheries of the plates. From these furrows, and at an angle with them, are sets of furrows extending to within an eighth of an inch of the peripheries of the plates, by which arrangement there is I the furrows B B and thence to the smooth surfaces D at the outer edges of the plates, which, being close together, allow none of the particles to escape unground. When the edges of the burrs grow dull, the plates are run together, and by revolving them slowly the teeth or edges on both plates are sharpened.

It is obvious that the operation of our improvements is not limited to the use of sectional plates, but is just as operative cast in one large plate.

Having described our invention, What we claim, and desire to secure by Letters Patent of the United States, is'- A millstone-burr composed of the sectional plates B, having compound convex and concave furrowed surfaces, the convex portions being close to the eye of the stone, and the fiat or smooth surfaces D on their outer edges, substantially as and for the purpose set forth and described.

In testimony that we claim the foregoing we append our signatures.

LORENZO I. TEED. CHARLES TEED.

WVitnesses:

Jos. HENDERSON, J OHN FERRIER. 

